v0.2.0

Two new core tools — fourteen in all — and new modes on seven of the existing ones, plus a
dashboard that lets you delete old keys and a hosted free tier of 1,000 calls per key per day.
Everything is additive: every call that worked on 0.1.0 returns the same shape on 0.2.0.

Added

New tools

• finance tool (13th core tool): emi (instalment, totals and amortisation schedule that
  reconciles to zero), compound (future value with optional per-period contributions and the
  effective annual rate), cagr, npv_irr (IRR by bisection), gst (inclusive/exclusive split
  into CGST/SGST or IGST, rounding difference reported) and percent (change vs percentage
  points, stacked vs additive discounts, exact bill splits). The rate's period and whether an
  amount is GST-inclusive are required, not guessed.
• color tool (14th core tool): convert between hex (3/4/6/8-digit), RGB, HSL, HSV/HSB,
  naive CMYK and Lab with alpha preserved; describe names the nearest of the 148 CSS colours
  by CIE76 ΔE and words the colour from fixed HSL bands; swatch returns a real PNG (stdlib
  zlib, 16–256 px, one colour or two side by side); contrast gives the WCAG 2.x ratio,
  AA/AAA for normal and large text and the smallest lightness change that passes; mix
  blends in sRGB or Lab; harmony rotates hue for complementary, analogous, triadic and
  split-complementary sets; nearest snaps to a caller's palette with the runner-up;
  simulate shows deuteranopia, protanopia and tritanopia (Viénot–Brettel–Mollon 1999);
  grayscale greys by rec709, rec601, lab, average or hsl with an optional ramp and strip.
  Bare triples such as 58, 26, 241 are refused with needs.options (rgb, hsl, hsv).

New modes and parameters

• datetime now takes a list as tz — zone names or {tz, label} objects — and answers with
  the shared instant as utc plus one full per-zone entry under zones, each carrying its
  label back. convert_tz accepts the same {tz, label} entries in to_tz. One round-trip
  for "what time is it in each of our offices right now"; the single-tz form is unchanged.
• datetime free_slots: common free slots for two or more participants in different time
  zones, from weekly windows (09:00–17:00 on mon…fri) or one-off local ranges, intersected
  in UTC through zoneinfo. Each slot is shown in every participant's local time and in UTC,
  per_day totals the overlap per date, a window spanning a DST change is expanded to its real
  length with a note in assumptions, and no common time is ok: true with slots: [] and a
  warning naming who never overlaps.
• convert fuel_economy: mpg_us / mpg_uk / km_per_l / l_per_100km with exact
  constants; a bare mpg is ambiguous (US or imperial gallon), and any conversion that crosses
  L/100 km states the inverse relation in assumptions.
• convert cooking: cups, tbsp, tsp, ml, fl oz ↔ g, kg, oz, lb. Mass ↔ volume needs
  ingredient, looked up in a built-in density table (18 staples; the grams-per-cup used are
  stated); a missing or unknown ingredient returns the table as needs.options. cup selects the
  US (240 ml, default and declared), metric, UK or Australian (20 ml tablespoon) system.
• convert sizes: category=shoe converts US men / US women / UK / EU / cm on a generic
  adult chart, snapping to the nearest half size with a warning; category=clothing maps XS–XXL
  to chest and waist cm bands for a chart chosen by region (us inch-based, eu EN 13402-3)
  and gender, both required. Every result warns that sizes are approximate and names the chart.
• numbers semver: compare or sort version strings as versions (1.10 > 1.9), with
  SemVer 2.0 pre-release precedence, build metadata carried but ignored for ordering, and a
  leading v / missing minor or patch tolerated and recorded in assumptions.
• text similarity: Levenshtein distance and a 0–1 ratio for a pair, or text + items to
  rank candidates and return the best match with its index — mapping typed input onto a menu,
  spotting near-duplicate names. Case-folded and whitespace-normalised by default, both stated.
• collections: every record input (items, a/b, data) also accepts CSV text — the
  delimiter is sniffed, the header row detected (first row with no numeric, date or boolean cell;
  has_header overrides), each field typed as number (exact Decimal, via numbers.parse),
  ISO date, boolean or text, and blank rows and N/A/-/null cells skipped and counted, all
  stated in assumptions; above 5,000 rows the call is refused. New table modes over the same
  input: filter (where predicates with the validate.assert vocabulary, compared in the
  field's type), pivot (by × pivot_columns, one aggregate of column, row and grand
  totals, empty cells null), running (cumulative total, restarting per by), outliers
  (Tukey hinges, 1.5×IQR, fences reported, at least 4 values), summarize (count/nulls/sum/avg/
  min/max/median for every numeric field, distinct counts for text, range for dates) and to_csv
  (delimiter, chosen columns). A lone numeric field is assumed for running/outliers and
  said so; several are ambiguous. decimals rounds computed values only; row-shaped results
  echo at most 500 rows with a warning, except to_csv.
• validate cidr: membership (network + value → contains, for an address or a smaller
  block) and overlap (a list of networks → every pair with equal / a_contains_b /
  b_contains_a / disjoint), plus a block's size, usable hosts, bounds and masks. Host bits
  set are read as the network and recorded in assumptions.
• validate id with kind=isbn returns both isbn10 and isbn13 for a valid number (a 979
  book has no ISBN-10 form).
• encode hash and checksum take expected and answer matches — compared in constant
  time against the hex, Base64 (or, for checksums, decimal) form, case- and whitespace-
  insensitive, with a sha256sum-style <digest> <file> line accepted as-is. A mismatch is
  ok: true, matches: false: an answer, not an error. hmac shares the same comparison.
• files file_hash: sha256 (default) / sha1 / md5 / blake2b / crc32 and the other hashlib
  algorithms, streamed in 1 MiB chunks so a file's size is bounded only by LEFTBRAIN_FILE_ROOTS,
  with bytes, the algorithm used, and expected → matches for verifying a download.

Keys and dashboard

• leftbrain-keys set --all --daily N [--rpm N] [--from-daily N] changes limits on every key —
  or, with --from-daily, only on keys still at an old default — so a moved default can be
  migrated without a database shell or touching keys set by hand. Prints how many keys changed.
• Dashboard Delete for a revoked or expired key: removes the row and its usage history for
  good (with a confirm). A key that still works must be revoked first; deletion is owner- and
  CSRF-checked like the other key routes.

Fixed

• Dashboard: keys issued before the server could show keys again (including the old
  POST /keys/signup rows, still named self-serve signup) are marked legacy and explained
  on the row instead of the bare "created before reveal was enabled". They no longer hold one of
  the owner's active-key slots, so a first sign-in that inherits three of them can still create a
  key. /keys/me output is unchanged.
• Demo endpoint: the 8 KB body cap now applies to chunked requests too, and deeply nested arguments return a contract invalid_input instead of a bare 500.
• Docker image build failed after the changelog was bundled into the wheel (CHANGELOG.md was not copied into the image).

Changed

• Free tier is 1,000 calls per key per day (was 5,000); LEFTBRAIN_DEFAULT_DAILY_QUOTA still overrides it. Every place the site quotes the limit — landing, sign-in, quickstart, the demo's 429 — now reads the configured value instead of a hard-coded number.
• Site shows loading skeletons on navigation, form submits and demo runs; the colour legend on docs pages was dropped.
• Docs key picker shows the key name only (prefix only for unnamed keys).
• Docs examples are labelled Request/Response and colour-coded: blue blocks are what you
  send, green blocks are what comes back, and a neutral block marks a setup command.